(19)
(11) EP 2 515 802 B1

(12) EUROPEAN PATENT SPECIFICATION

(45) Mention of the grant of the patent:
27.04.2016 Bulletin 2016/17

(21) Application number: 10807639.9

(22) Date of filing: 22.12.2010
(51) International Patent Classification (IPC): 
A61F 2/50(2006.01)
(86) International application number:
PCT/GB2010/052192
(87) International publication number:
WO 2011/077156 (30.06.2011 Gazette 2011/26)

(54)

METHOD AND APPARATUS FOR COLOURING A COSMETIC COVERING

VERFAHREN UND VORRICHTUNG ZUR FÄRBUNG EINES KOSMETISCHEN ÜBERZUGS

PROCÉDÉ ET APPAREIL DE COLORATION D'UN REVÊTEMENT COSMÉTIQUE


(84) Designated Contracting States:
AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

(30) Priority: 24.12.2009 GB 0922603

(43) Date of publication of application:
31.10.2012 Bulletin 2012/44

(73) Proprietor: Touch Bionics Limited
Livingston EH53 0TH (GB)

(72) Inventor:
  • GILL, Hugh
    Strathclyde PA2 8PY (GB)

(74) Representative: Cooper, John et al
Murgitroyd & Company Scotland House 165-169 Scotland Street
Glasgow G5 8PL
Glasgow G5 8PL (GB)


(56) References cited: : 
EP-A2- 0 947 899
US-A1- 2002 016 631
US-A- 6 111 973
US-A1- 2006 229 755
   
       
    Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art. 99(1) European Patent Convention).


    Description

    Field of the invention



    [0001] The present invention relates to a method and apparatus for colouring a cosmetic covering and in particular, but not exclusively, a method and apparatus for colouring a cosmetic covering for a prosthesis.

    Background to the invention



    [0002] Cosmetic coverings for prostheses are normally coloured to provide as life-like appearance as possible. One approach involves a clinician determining the appropriate colouring for a cosmetic covering by eye, e.g. by viewing the skin of the prosthesis wearer, and mixing differently coloured paints to achieve a match to the determined colours. The paint may be mixed from a palette consisting, for example, of eighty-four colours with each colour having two hundred and fifty six shades. The clinician then paints the cosmetic covering by hand. However, there is often no high degree of consistency in the colours from palette to palette. Also, clinicians will often see colours differently on account of a colour vision deficiency on the part of the clinician or on account of artificial lighting being used when the clinician is viewing the skin of the prosthesis wearer to determine the appropriate colouring. This approach typically results in 30% of painted cosmetic coverings being rejected.

    [0003] Another approach involves a clinician taking colour readings with a spectrophotometer at six to ten different locations on the prosthesis wearer's skin to determine appropriate colours for a cosmetic covering. The colour values, e.g. Red, Blue, Yellow (RBY) values, for each location are determined by a computer from the spectrophotometer readings and differently coloured paints are mixed in dependence on the determined colour values.

    [0004] One particular known method of colouring a cosmetic covering is disclosed in US2006-0229755.

    [0005] The present inventor has appreciated shortcomings of the above known approaches.

    [0006] According to a first aspect of the present invention, there is provided a method of colouring a cosmetic covering in accordance with claim 1.

    [0007] The cosmetic covering may be configured to cover a prosthesis, such as a hand prosthesis, or foot prosthesis, for example. More specifically, the cosmetic covering may be a surface of the cosmetic covering. In one form, the at least one mixed paints may be applied by a person, e.g. using a brush. In another form, the at least one mixed paints may be applied by paint applying apparatus, such as spray painting apparatus.

    [0008] Alternatively or in addition, the method may comprise acquiring a plurality of different images of the part of the human or animal body. For example, where the part is a hand, an image of the top of the hand, an image of the bottom (i.e. palm side) of the hand and an image of the thumb side of the hand may be acquired. Hence, each of the plurality of acquired digital colour images may be transformed by the calibration transform.

    [0009] Alternatively or in addition, the method may further comprise disposing the part of the human or animal body in relation to the image acquisition apparatus and displaying an image of the part acquired by the image acquisition apparatus on display apparatus, such as on a Visual Display Unit (VDU). The present step may be carried out before the step of acquiring an image of the part to provide the digital colour image. Hence, the present step may be used to determine whether or not the part is properly disposed in relation to the image acquisition apparatus and, if not, the part may be moved or its orientation changed to achieve proper disposition.

    [0010] Alternatively or in addition, the method may comprise receiving the body part in an enclosed space.

    [0011] More specifically, the enclosed space may be illuminated in a controlled fashion by means of a light source. Alternatively or in addition, the enclosed space may be illuminated by a light source configured to provide for substantially uniform illumination in a plane, e.g. a plane extending generally perpendicular to a path between the image acquisition apparatus and the part of the human or animal body.

    [0012] Alternatively or in addition, the enclosed space may be illuminated by a light source configured to be disposed proximate the image acquisition apparatus. More specifically, the light source may be configured to receive a lens of the image acquisition apparatus such a light emitting part of the light source is disposed around the lens. Alternatively or in addition, the light source may comprise a light emitting part of annular form. The light emitting part may comprise a plurality of Light Emitting Diodes (LEDs) disposed in relation to each other in a generally square pattern.

    [0013] Alternatively or in addition, the data acquisition apparatus may comprise a digital camera. More specifically, the digital camera may be a true colour digital camera. The true colour nature of the digital camera may be afforded by a characteristic of an optical lens disposed between the part of the human or animal body and an aperture of the digital camera.

    [0014] Alternatively or in addition, the apparatus may be configured to control the camera in respect of at least one of: at least one RGB analogue gain; at least one of HSV values corresponding to RGB values; exposure time; a gain of the camera; gamma; white balance; light power; contrast; and saturation.

    [0015] Alternatively or in addition, the method may further comprise: displaying the compensated digital colour image on display apparatus; and selecting a plurality of different areas on the compensated digital colour image. The plurality of different areas may be selected by an operator, e.g. by means of pointing at each area with a mouse and clicking.

    [0016] More specifically, colour characteristics of the colours within the plurality of different selected areas may be conveyed to the paint mixing apparatus of the first aspect, which is operative to mix a plurality of paints of different colours in dependence on the colour characteristics to produce a plurality of mixed paints. The colour characteristics may be Red, Blue and Yellow (RBY) values determined from the plurality of different selected areas, e.g. by means of processing apparatus. The plurality of mixed paints may correspond respectively to colours within the plurality of different selected areas.

    [0017] Alternatively or in addition, the paint mixing apparatus may comprise a plurality of paint dispensers, each paint dispenser containing a paint of a different colour.

    [0018] Different batches of paint of a particular colour may be of a slightly different colour. Hence, it may be desired to provide for colour consistency from batch to batch. Therefore, alternatively or in addition, the method may further comprise determining a colour of a batch of paint, e.g. a fresh batch, by means of colour determining apparatus. The colour determining apparatus may comprise apparatus, such as a spectrophotometer, that is operative to determine a bulk colour value (e.g. at a measurement location) for the paint batch. The colour determining apparatus may be operative to determine the Red, Blue, Yellow (RBY) values of the paint.

    [0019] More specifically, the method may further comprise comparing the determined colour of the paint with a predetermined colour, e.g. as determined by measuring the colour of another batch of paint, such as the batch most recently present in the colour mixing apparatus.

    [0020] Alternatively or in addition, the method may further comprise changing proportions of paints of different colours used to produce a paint mixture in dependence on the determined colour of the batch of paint. Hence, for example, relative amounts of Red Blue and Yellow paints used to form the plurality of mixed paints may be changed to take account of a change in colour from one batch of paints to another.

    [0021] Alternatively or in addition, the method may further comprise: conveying the colour compensated digital colour image to printing apparatus; and printing the colour compensated digital colour image by means of the printing apparatus. The colour compensated digital colour image may be wirelessly conveyed to the printing apparatus.

    [0022] More specifically, the method may further comprise acquiring by image acquisition apparatus an image of an image printed by the printing apparatus to provide a digital colour printed image. The image acquisition apparatus may comprise a digital camera. Preferably, a calibration transform may have been determined for the image acquisition apparatus. Hence, any contrary effect as regards colour caused by the image acquisition apparatus and/or lighting when the image acquisition apparatus is operative may be minimised. The printed image may comprise a colour chart, e.g. a colour chart stored in processing apparatus. The digital colour printed image, e.g. of the colour chart, may be conveyed to processing apparatus.

    [0023] Alternatively or in addition, the method may comprise: determining a printer calibration transform for colours of an image, e.g. of a colour chart, printed by the printer; and transforming a colour compensated digital colour image in dependence on the printer calibration transform. Thus, the printer may print an image that properly reflects the true colours of the colour compensated digital colour image.

    [0024] According to a second aspect of the present invention, there is provided apparatus for colouring a cosmetic covering in accordance with claim 14.

    [0025] The cosmetic covering may be configured to cover a prosthesis, such as a hand prosthesis. More specifically, the cosmetic covering may be a surface of the cosmetic covering. In one form, the at least one mixed paints may be applied by a person, e.g. using a brush. In another form, the at least one mixed paints may be applied by paint applying apparatus, such as spray painting apparatus.

    [0026] More specifically, the processing apparatus of the second aspect may comprise a computer, such as a Personal Computer (PC). The image acquisition apparatus may comprise a colour digital camera and may be configured to convey the digital colour image to the processing apparatus for processing thereon.

    [0027] Further embodiments of the second aspect of the present invention may comprise one or more features of the first aspect of the present invention.

    Brief description of the drawings



    [0028] The present invention will now be described by way of example only with reference to the following drawings, of which:

    Figure 1A is a diagram of apparatus according to the present invention;

    Figure 1B shows the disposition of LEDs with respect to each other and the camera;

    Figure 2 is a flow chart representation of a method of colouring a cosmetic covering according to the present invention;

    Figure 3 is a flow chart representation of a method of compensating for variation in pigment colours;

    Figure 4 is a flow chart representation of a method of colour compensating a printer; and

    Figure 5 shows un-transformed and transformed RGB curves.


    Specific description



    [0029] Apparatus for colouring a cosmetic covering 10 is shown in Figure 1A. The apparatus 10 comprises an enclosure, which defines an entirely enclosed space, with the exception of an aperture 14 of sufficient size and shape to allow a part of body, such as a hand, to be received within the enclosure. At least most of the interior surface of the enclosure is white. The apparatus also comprises an arrangement of LEDs 16, each LED being an Osram Golden Dragon Plus, white, LW W5AM-JYKY-5K8L from Osram GmbH, Hellabrunner Strasse 1, 81543 München, Germany, and a 9.1 MP digital colour camera 18, namely a microscope c mount camera MDCM-900 from Mueller Optronic of Am Hugel 10A, 99084 Erfurt, Germany. A 3 volt power supply provides electrical power for the LEDs. A 1 Ohm resistor is in series between each LED and the power supply. The digital colour camera 18 comprises a true colour low magnification video lens, namely a Navitar NMV-5WA standard C mount lens from Navitar Inc. of 200 Commerce Drive, Rochester NY 14623, USA. The disposition of the LEDs 16 in relation to each other and the camera 18 is shown in Figure 1B. As can be seen from Figure 1B, the LEDs 16 form a generally square pattern with the camera 18 substantially at the centre of the square pattern. The camera and the LEDs are located in the roof of the enclosure such that the LEDs illuminate the interior of the enclosure and the camera is capable of acquiring an image of the body part located within the enclosure. An output from the digital colour camera 18 is electrically connected to a Personal Computer (PC) 20, which comprises a Visual Display Unit (VDU) 22. The Personal Computer is in communication with an Epson R2880 printer 24, with communication being either wired or wireless depending on whether the printer is in the same locale as the Personal Computer or at a distant location. Software running on the PC is operative to control and operate the camera 18. The software has been developed for Microsoft Windows XP or higher using Visual Studio 2008 and Direct Show SDK. The Direct Show SDK provide for the interface with the camera with camera set-up controls provided by Mueller Optronic. The software is operative to provide a hardware accelerated live view of the body part inside the enclosure and controls for adjusting the camera parameters. The controls are only displayed when the apparatus is in a set-up mode to thereby reduce the likelihood of the operator adjusting the controls so as to compromise proper operation of the apparatus. Likewise, the default control settings for the camera under particular lighting conditions are hard-coded into the software to reduce the likelihood of operator adjustments that might compromise proper operation of the apparatus. Design of such software is readily with the scope of the ordinary design skills of the person skilled in the art. The default control settings for the camera comprise the RGB (Red Green Blue) channel analogue gains, HSV (Hue Saturation and Value) representations of the RGB values, exposure time, the gain of the camera and gamma, contrast and saturation. The default control settings are determined by taking images of a Gretag MacBeth colour chart located in the enclosure and adjusting the control settings until the desired quality of image is obtained. The apparatus 10 further comprises paint mixing apparatus 26, which is operative to mix differently coloured pigments to provide a plurality of pigment mixtures 28. The differently coloured pigments are contained within a plurality of respective containers within the paint mixing apparatus. The containers are supported on a carousel arrangement so that each container is moved proximate a mixing container so that the container's contents may be dispensed into the mixing container. The contents of a container are dispensed by means of a syringe pump. Hence, the paint mixing apparatus 26 comprises a container for each of Red, Blue and Yellow, a container containing clear silicone and a container containing white silicone. When a particular colour is obtained, the mixture typically comprises about 80% clear silicone, about 18% white silicone and about 2% for each of the Red, Blue and Yellow. The design of the paint mixing apparatus is readily within the ordinary design skills of the person of skill in the art. The paint mixing apparatus 26 is in communication with the Personal Computer 20, with communication being either wired or wireless depending on whether the paint mixing apparatus is in the same locale as the Personal Computer or at a distant location.

    [0030] A method according to the present invention will now be described with reference to Figure 2, which represents steps of the method in flow-chart form 40. A Munsell Colour XRite Gretag MacBeth colour chart is placed in the enclosure 12 of Figure 1A and an image of the colour chart is acquired 42 by the digital colour camera 18. The colour chart image is conveyed to the Personal Computer (PC) 20. The PC is operative to determine a colour difference between each of the colour values in the colour chart image with each corresponding actual colour value for the colour chart stored in the PC. Each colour difference is translated into RGB positional space (3D colour space) such that the colour differences are in the form of sparse points in a Look Up Table (LUT) for each of Red, Green and Blue values. The PC is operative to interpolate between the sparse points in each LUT with a Catmull-ROM point fitting curve being used. The resulting LUT values are filtered by means of a rolling average filter with twelve taps. The thus determined LUTs are used to effect a calibration transformation of subsequently acquired images to thereby compensate for inaccuracies in the colour representation arising from acquisition by the digital colour camera. In other words, transformation of the colour chart image with the LUT based calibration transform produces a compensated colour chart image that more faithfully represents the true colours contained in the colour chart.

    [0031] The calibration transform may also include determining calibrations for one or more of the group comprising: light power, based on the perceived brightness of one or more greyscale values; saturation; gamma function; and contrast function.

    [0032] The camera 18 may also include an auto white balance to compensate for variation in camera sensitivity. The step of compensating for the variation in camera sensitivity may be performed before the brightness calibration is determined and corrected.

    [0033] The calibration transform may satisfy the requirements of an industry standard profile, such as those set by the International Colour Consortium (ICC). This is termed a colour model of the camera response.

    [0034] Un-transformed and transformed RGB curves are shown in Figure 5. In Figure 5, the un-transformed curves for each of Red, Green and Blue are indicated by reference numeral 100 and the transformed curves are indicated by reference numeral 102. As can be seen, transformed curves are closer to the ideal straight, diagonal line than the un-transformed curves. The above described calibration procedure is normally only carried out at a conclusion to manufacture of apparatus according to the invention. However, the calibration procedure may be carried out in the field if the configuration of the apparatus is changed, e.g. if there is a change in lighting conditions or if there is a change in ambient temperature that is sufficient to warrant re-calibration.

    [0035] Referring again to Figure 2, the wearer of a prosthetic right hand places his left hand in the enclosure 12 of Figure 1A. The digital colour camera is operative to acquire a series of images at a sampling rate of about one second. The series of images are displayed on the VDU 22 by way of the PC 20. A clinician inspects the displayed images to determine whether or not a full image of the hand is displayed and whether or not the hand is properly oriented within the enclosure. If not, the wearer moves his hand within the enclosure to remedy the lack of proper positioning. When the hand is positioned properly, operator operates the PC, e.g. by means of a "capture" button on the software interface, such that the digital colour image displayed at that time is stored in the PC. Then the PC 20 is operative to transform the stored digital colour with the calibration transform to produce a compensated digital colour image 48. Further images of the hand, e.g. bottom and side images, may then be acquired and transformed as described above and depending on requirements. Thereafter the compensated digital colour image is displayed on the VDU 50 and the clinician, or painter, selects six to ten different areas on the image 52. The PC is then operative to determine the colour values of the selected areas in terms of Red, Blue, Yellow (RBY) values for the selected areas 54. Alternatively, RBY colour values may be determined on the basis of a predetermined recipe and without the clinician selecting the different areas. The colour values are conveyed 56 to the paint mixing apparatus 26 and the paint mixing apparatus 26 is operative to produce paint mixtures of the correct colour 58 in dependence on the received colour values. When the paint mixing is complete, the clinician, or painter, paints the surface of the cosmetic covering with the paint mixtures 60. Data for acquired images and corresponding colour values are encrypted to reduce the likelihood of tampering and the proper operation of the apparatus being compromised.

    [0036] The colour of paint of a particular colour may vary from batch to batch. Hence and referring to Figure 3, the colour value of a fresh batch of paint is determined with a spectrophotometer 72. A colour value determined by the spectrophotometer is conveyed to the PC 20, which stores a desired colour value for the particular colour in question, e.g. a colour value for a previously used batch of paint of the same colour. The PC is operative to compare the spectrophotometer determined colour value with the stored colour value 74 and to change a compensated digital colour image (see step 48 in Figure 2) to take account of a variation in the colour value. Hence, when the paint mixing apparatus 26 is operative to mix paints in dependence on the compensated digital colour image variations in paint colour from batch to batch can be compensated for.

    [0037] It is often desirable to provide a printed copy of an acquired image of wearer's hand, e.g. for the purposes of the clinician or for inspection by the wearer himself. The International Colour Consortium (ICC) colour profile for the Epson R2880 printer 24 is set for Premium Luster paper as the default Image Colour Management (ICM) profile upon conclusion of manufacture of apparatus according to the invention. During use, the ICM settings provide for faithful printing of stored images. However, the printer 24 may be liable under certain circumstances to introduce errors in the reproduction of the colours of the acquired image. Therefore, calibration may be desired. Hence and referring to Figure 4 a true Gretag MacBeth colour chart stored in the PC 20 is printed with the printer 24, 82. Then the digital colour camera 18 is used to acquire an image of the printed image and the acquired image is conveyed to the PC. The colour values in the acquired image of the colour chart are compared with the respective colour values in the stored colour chart. The PC is then operative to determine a printer calibration transform 84 in dependence on the colour value comparisons, with the printer calibration transform being effective to compensate for inaccuracies in the colour representation arising from printing with the printer. Hence and referring to step 48 in Figure 2, a compensated image of the wearer's hand is conveyed to the printer 82, the compensated image is transformed with the printer calibration transform 88 to take account of printer inaccuracies and the further compensated image is printed with the printer 88.

    [0038] Following calibration of the camera as is described above, an image of a Gretag MacBeth colour chart was acquired and printed. A spectrophotometer was used to determine colour values for each colour patch of the Gretag MacBeth colour chart and of the printed image of the Gretag MacBeth colour chart and the differences between corresponding values in the two sets of measurements were determined. The mean sum of the absolute differences was then determined to thereby provide a percentage error for the printed image as a whole. By following this procedure, the apparatus according to the invention was shown to have an error of substantially 5.76%. It should be noted that it is undesirable for the calibration transform to provide for ideal calibration, i.e. such that the values in each LUT describe a straight, diagonal line. This is because ideal calibration may involve RGB values becoming negative, i.e. the values may become de-saturated, with the consequence that image quality is reduced.

    [0039] The apparatus and method according to the present invention may be employed in other applications. For example, the apparatus and method may be used in the cosmetics industry or in medical diagnosis. More specifically, the apparatus may be used to compare skin before and after the application of cosmetics to provide feedback to a user as to the appropriateness of the cosmetics applied. Alternatively, the apparatus may be used to detect skin colour profiles that are indicative of disease. An ultraviolet camera may be used instead of the colour camera 18 of Figure 1A to see below the surface of the skin. Such an ultraviolet camera may be particularly useful in detecting skin conditions that are not evident from an inspection of the skin surface.


    Claims

    1. A method of colouring a cosmetic covering (10), the method comprising:

    acquiring an image of a part of a human or animal body with an image acquisition apparatus (18) to provide a digital colour image;

    characterised in that the method further comprises the steps of:

    acquiring an image of a colour chart with the image acquisition apparatus (18) to provide a colour chart image;

    determining a calibration transform for colours of the image acquired by the image acquisition apparatus (18) in dependence on the colour chart image and colour values represented in the colour chart, wherein the calibration transform includes transformations for each of Red, Green and Blue values and each Red, Green and Blue transformation includes a Look Up Table (LUT), wherein each LUT is determined by sparsely populating the LUT with colour differences between each of the colour values in the colour chart image and each corresponding actual colour for the colour chart and interpolating between the sparse points;

    transforming the digital colour image with the calibration transform to provide a colour compensated digital colour image (48);

    conveying at least one colour characteristic of at least one colour within the colour compensated digital colour image (48) to a paint mixing apparatus (26), which is operative to mix a plurality of paints of different colours in dependence on the at least one colour characteristic to produce at least one mixed paint (60); and

    applying the at least one mixed paint (60) to a cosmetic covering (10).


     
    2. A method according to claim 1 comprising acquiring a plurality of different images of the part of the human or animal body.
     
    3. A method according to claim 1 or claim 2 further comprising the step of disposing the part of the human or animal body in relation to the image acquisition apparatus (18) and displaying an image of the part acquired by the image acquisition apparatus on display apparatus (22), the step being carried out before the step of acquiring an image of the part to provide the digital colour image.
     
    4. A method according to any preceding claim, in which the method further comprises: displaying the compensated digital colour image (48) on display apparatus (22); and selecting a plurality of different areas on the compensated digital colour image (48).
     
    5. A method according to claim 4, in which colour characteristics of the colours within the plurality of different selected areas are conveyed to the paint mixing apparatus (26) to produce a plurality of mixed paints (60).
     
    6. A method according to claim 5 further comprising applying the plurality of mixed paints (60) to the cosmetic covering (10).
     
    7. A method according to any preceding claim, in which the paint mixing apparatus (26) comprises a plurality of paint dispensers, each paint dispenser containing a paint of a different colour.
     
    8. A method according to claim 7 further comprising determining a colour of a batch of paint by means of colour determining apparatus, the colour determining apparatus comprising apparatus that is operative to determine a bulk colour value for the paint batch.
     
    9. A method according to claim 8 further comprising comparing the determined colour of the paint with a predetermined colour.
     
    10. A method according to claim 8 or 9 further comprising changing proportions of paints of different colours used to produce a paint mixture in dependence on the determined colour of the batch of paint.
     
    11. A method according to any preceding claim further comprising: conveying the colour compensated digital colour image (48) to printing apparatus (24); and printing the colour compensated digital colour image (48) by means of the printing apparatus (24).
     
    12. A method according to claim 11 further comprising acquiring by image acquisition apparatus (18) an image of an image printed by the printing apparatus (24) to provide a digital colour printed image.
     
    13. A method according to claim 12 further comprising: determining a printer calibration transform (84) for colours of an image printed by the printer (24); and transforming a colour compensated digital colour image (48) in dependence on the printer calibration transform (84).
     
    14. Apparatus for colouring a cosmetic covering (10), the apparatus comprising:

    image acquisition apparatus (18) operative to acquire an image of a part of a human or animal body to provide a digital colour image;

    characterised in that the image acquisition apparatus (18) is also operative to acquire an image of a colour chart to provide a colour chart image, and the apparatus further comprises:

    processing apparatus (20) operative to determine a calibration transform for colours of an image acquired by the image acquisition apparatus (18) in dependence on the colour chart image and colour values represented in the colour chart, wherein the calibration transform includes transformations for each of Red, Green and Blue values and each Red, Green and Blue transformation includes a Look Up Table (LUT), wherein each LUT is determined by sparsely populating the LUT with colour differences between each of the colour values in the colour chart image and each corresponding actual colour for the colour chart and interpolating between the sparse points,

    the processing apparatus (20) being further operative to transform the digital colour image with the calibration transform to provide a colour compensated digital colour image (48);

    paint mixing apparatus (26) operative to mix a plurality of paints of different colours in dependence on at least one colour characteristic of at least one colour within the colour compensated digital colour image (48) to produce at least one mixed paint (60); and

    paint applying apparatus operative to apply the at least one mixed paint to a cosmetic covering (10).


     


    Ansprüche

    1. Ein Verfahren zum Färben eines kosmetischen Überzugs (10), wobei das Verfahren Folgendes beinhaltet:

    Aufnehmen eines Bildes von einem Teil eines menschlichen oder tierischen Körpers mit einem Bildaufnahmegerät (18) zur Bereitstellung eines digitalen Farbbildes;

    dadurch gekennzeichnet, dass das Verfahren weiterhin die folgenden Schritte beinhaltet:

    Aufnehmen eines Bildes von einer Farbtafel mit dem Bildaufnahmegerät (18) zur Bereitstellung eines Farbtafelbildes;

    Bestimmen einer Kalibrierungstransformation für Farben des von dem Bildaufnahmegerät (18) aufgenommenen Bildes in Abhängigkeit von dem Farbtafelbild und den Farbwerten, die in der Farbtafel dargestellt sind, wobei die Kalibrierungstransformation Transformationen für Werte von jeweils Rot, Grün und Blau umfasst und die Transformation von jeweils Rot, Grün und Blau eine Nachschlagetabelle (LUT, Look-Up-Table) umfasst, wobei jede LUT durch dünnes Besetzen der LUT mit Farbunterschieden zwischen den jeweiligen Farbwerten in dem Farbtafelbild und jeder entsprechenden eigentlichen Farbe für die Farbtafel und Interpolieren zwischen den dünn besetzten Punkten bestimmt wird;

    Transformieren des digitalen Farbbildes mit der Kalibrierungstransformation zur Bereitstellung eines farbkompensierten digitalen Farbbildes (48);

    Übertragen mindestens einer Farbcharakteristik von mindestens einer Farbe innerhalb des farbkompensierten digitalen Farbbildes (48) auf ein Anstrichfarbenmischgerät (26), das betriebsfähig ist, um eine Vielzahl von Anstrichfarben unterschiedlicher Farben in Abhängigkeit von der mindestens einen Farbcharakteristik zu mischen, um mindestens eine Mischanstrichfarbe (60) zu erzeugen; und

    Auftragen der mindestens einen Mischanstrichfarbe (60) auf einen kosmetischen Überzug (10).


     
    2. Verfahren gemäß Anspruch 1, das das Aufnehmen einer Vielzahl von unterschiedlichen Bildern von dem Teil des menschlichen oder tierischen Körpers beinhaltet.
     
    3. Verfahren gemäß Anspruch 1 oder Anspruch 2, das weiterhin den Schritt des Anordnens des Teils von dem menschlichen oder tierischen Körper bezüglich des Bildaufnahmegeräts (18) und des Anzeigens eines Bildes des von dem Bildaufnahmegerät aufgenommenen Teils auf einem Anzeigegerät (22) beinhaltet, wobei der Schritt vor dem Schritt des Aufnehmens eines Bildes des Teils zur Bereitstellung des digitalen Farbbildes durchgeführt wird.
     
    4. Verfahren gemäß einem der vorhergehenden Ansprüche, wobei das Verfahren weiterhin Folgendes beinhaltet: Anzeigen des kompensierten digitalen Farbbildes (48) auf dem Anzeigegerät (22); und Auswählen einer Vielzahl von unterschiedlichen Bereichen auf dem kompensierten digitalen Farbbild (48).
     
    5. Verfahren gemäß Anspruch 4, wobei die Farbcharakteristiken der Farben innerhalb der Vielzahl von unterschiedlichen ausgewählten Bereichen auf das Anstrichfarbenmischgerät (26) übertragen werden, um eine Vielzahl von Mischanstrichfarben (60) zu erzeugen.
     
    6. Verfahren gemäß Anspruch 5, das weiterhin das Auftragen der Vielzahl von Mischanstrichfarben (60) auf einen kosmetischen Überzug (10) beinhaltet.
     
    7. Verfahren gemäß einem der vorhergehenden Ansprüche, wobei das Anstrichfarbenmischgerät (26) eine Vielzahl von Anstrichfarbenabgabevorrichtungen beinhaltet, wobei jede Anstrichfarbenabgabevorrichtung eine Anstrichfarbe mit einer anderen Farbe enthält.
     
    8. Verfahren gemäß Anspruch 7, das weiterhin das Bestimmen einer Farbe aus einem Satz Anstrichfarben mittels eines Farbbestimmungsgeräts beinhaltet, wobei das Farbbestimmungsgerät ein Gerät beinhaltet, das betriebsfähig ist, um einen Mengenfarbwert für den Satz Anstrichfarben zu bestimmen.
     
    9. Verfahren gemäß Anspruch 8, das weiterhin das Vergleichen der bestimmten Farbe der Anstrichfarbe mit einer vorbestimmten Farbe beinhaltet.
     
    10. Verfahren gemäß Anspruch 8 oder 9, das weiterhin das Ändern der Verhältnisse von Anstrichfarben unterschiedlicher Farben, die verwendet werden, um ein Anstrichfarbengemisch zu erzeugen, in Abhängigkeit von der bestimmten Farbe des Satzes Anstrichfarben beinhaltet.
     
    11. Verfahren gemäß einem der vorhergehenden Ansprüche, das weiterhin Folgendes beinhaltet: Übertragen des farbkompensierten digitalen Farbbildes (48) auf ein Druckgerät (24); und Drucken des farbkompensierten digitalen Farbbildes (48) mittels des Druckgerätes (24).
     
    12. Verfahren gemäß Anspruch 11, das weiterhin das Aufnehmen, durch das Bildaufnahmegerät (18), eines Bildes von einem von dem Druckgerät (24) gedruckten Bild zur Bereitstellung eines digitalen Farbdruckbildes beinhaltet.
     
    13. Verfahren gemäß Anspruch 12, das weiterhin Folgendes beinhaltet: Bestimmen einer Druckerkalibrierungstransformation (84) für von dem Drucker (24) gedruckte Farben; und Transformieren eines farbkompensierten digitalen Farbbildes (48) in Abhängigkeit von der Druckerkalibrierungstransformation (84).
     
    14. Ein Gerät zum Färben eines kosmetischen Überzugs (10), wobei das Gerät Folgendes beinhaltet:

    das Bildaufnahmegerät (18), das betriebsfähig ist, um ein Bild von einem Teil eines menschlichen oder tierischen Körpers zur Bereitstellung eines digitalen Farbbildes aufzunehmen;

    dadurch gekennzeichnet, dass das Bildaufnahmegerät (18) außerdem betriebsfähig ist, um ein Bild von einer Farbtafel zur Bereitstellung eines Farbtafelbildes aufzunehmen, und wobei das Gerät ferner Folgendes beinhaltet:

    ein Verarbeitungsgerät (20), das betriebsfähig ist, um eine Kalibrierungstransformation für Farben des von dem Bildaufnahmegerät (18) aufgenommenen Bildes in Abhängigkeit von dem Farbtafelbild und den Farbwerten, die in der Farbtafel dargestellt sind, zu bestimmen, wobei die Kalibrierungstransformation Transformationen für Werte von jeweils Rot, Grün und Blau umfasst und die Transformation von jeweils Rot, Grün und Blau eine Nachschlagetabelle (LUT, Look-Up-Table) umfasst, wobei jede LUT durch dünnes Besetzen der LUT mit Farbunterschieden zwischen den jeweiligen Farbwerten in dem Farbtafelbild und jeder entsprechenden eigentlichen Farbe für die Farbtafel und Interpolieren zwischen den dünn besetzten Punkten bestimmt wird,

    wobei das Verarbeitungsgerät (20) weiterhin betriebsfähig ist, um das digitale Farbbild mit der Kalibrierungstransformation zur Bereitstellung eines farbkompensierten digitalen Farbbildes (48) zu transformieren;

    das Anstrichfarbenmischgerät (26) betriebsfähig ist, um eine Vielzahl von Anstrichfarben unterschiedlicher Farben in Abhängigkeit von mindestens einer Farbcharakteristik von mindestens einer Farbe innerhalb des farbkompensierten digitalen Farbbildes (48) zu mischen, um mindestens eine Mischanstrichfarbe (60) zu erzeugen; und

    das Anstrichfarbenauftragungsgerät betriebsfähig ist, um die mindestens eine Mischanstrichfarbe auf einen kosmetischen Überzug (10) aufzutragen.


     


    Revendications

    1. Un procédé de coloration d'un revêtement cosmétique (10), le procédé comprenant :

    l'acquisition d'une image d'une partie d'un corps animal ou humain avec un appareil d'acquisition d'images (18) pour fournir une image couleur numérique ;

    caractérisé en ce que le procédé comprend en outre les étapes consistant à :

    acquérir une image d'une échelle des couleurs avec l'appareil d'acquisition d'images (18) pour fournir une image d'échelle des couleurs ;

    déterminer une transformation d'étalonnage pour les couleurs de l'image acquise par l'appareil d'acquisition d'images (18) en fonction de l'image d'échelle des couleurs et des valeurs de couleur représentées dans l'échelle des couleurs, dans lequel la transformation d'étalonnage inclut des transformations pour chacune des valeurs Rouge, Vert et Bleu et chaque transformation de Rouge, Vert et Bleu inclut une palette de couleurs (Look Up Table, LUT), dans lequel chaque LUT est déterminée en peuplant la LUT de manière clairsemée avec des différences de couleur entre chacune des valeurs de couleur dans l'image d'échelle des couleurs et chaque couleur réelle correspondante pour l'échelle des couleurs et en interpolant entre les points clairsemés ;

    transformer l'image couleur numérique avec la transformation d'étalonnage pour fournir une image couleur numérique à couleurs compensées (48) ;

    transmettre au moins une caractéristique de couleur d'au moins une couleur à l'intérieur de l'image couleur numérique à couleurs compensées (48) à un appareil de mélange de peinture (26), lequel est opérant pour mélanger une pluralité de peintures de couleurs différentes en fonction de l'au moins une caractéristique de couleur afin de produire au moins une peinture mélangée (60) ; et

    appliquer l'au moins une peinture mélangée (60) sur un revêtement cosmétique (10).


     
    2. Un procédé selon la revendication 1 comprenant l'acquisition d'une pluralité d'images différentes de la partie du corps animal ou humain.
     
    3. Un procédé selon la revendication 1 ou la revendication 2 comprenant en outre l'étape consistant à disposer la partie du corps animal ou humain en relation à l'appareil d'acquisition d'images (18) et à afficher une image de la partie acquise par l'appareil d'acquisition d'images sur un appareil d'affichage (22), l'étape étant réalisée avant l'étape consistant à acquérir une image de la partie pour fournir l'image couleur numérique.
     
    4. Un procédé selon n'importe quelle revendication précédente, dans lequel le procédé comprend en outre : l'affichage de l'image couleur numérique compensée (48) sur l'appareil d'affichage (22) ; et la sélection d'une pluralité de zones différentes sur l'image couleur numérique compensée (48).
     
    5. Un procédé selon la revendication 4, dans lequel les caractéristiques de couleur des couleurs à l'intérieur de la pluralité de zones sélectionnées différentes sont transmises à l'appareil de mélange de peinture (26) pour produire une pluralité de peintures mélangées (60).
     
    6. Un procédé selon la revendication 5 comprenant en outre l'application de la pluralité de peintures mélangées (60) sur le revêtement cosmétique (10).
     
    7. Un procédé selon n'importe quelle revendication précédente, dans lequel l'appareil de mélange de peinture (26) comprend une pluralité de distributeurs de peinture, chaque distributeur de peinture contenant une peinture d'une couleur différente.
     
    8. Un procédé selon la revendication 7 comprenant en outre la détermination d'une couleur d'un lot de peinture au moyen d'un appareil de détermination de couleur, l'appareil de détermination de couleur constituant un appareil qui est opérant pour déterminer une valeur de couleur volumique pour le lot de peinture.
     
    9. Un procédé selon la revendication 8 comprenant en outre la comparaison de la couleur déterminée de la peinture avec une couleur prédéterminée.
     
    10. Un procédé selon la revendication 8 ou la revendication 9 comprenant en outre le changement des proportions des peintures de différentes couleurs utilisées pour produire un mélange de peinture en fonction de la couleur déterminée du lot de peinture.
     
    11. Un procédé selon n'importe quelle revendication précédente comprenant en outre : la transmission de l'image couleur numérique à couleurs compensées (48) à un appareil d'impression (24) ; et l'impression de l'image couleur numérique à couleurs compensées (48) au moyen de l'appareil d'impression (24).
     
    12. Un procédé selon la revendication 11 comprenant en outre l'acquisition par l'appareil d'acquisition d'images (18) d'une image d'une image imprimée par l'appareil d'impression (24) pour fournir une image imprimée couleur numérique.
     
    13. Un procédé selon la revendication 12 comprenant en outre : la détermination d'une transformation d'étalonnage d'imprimante (84) pour les couleurs d'une image imprimée par l'imprimante (24) ; et la transformation d'une image couleur numérique à couleurs compensées (48) en fonction de la transformation d'étalonnage d'imprimante (84).
     
    14. Appareil pour colorer un revêtement cosmétique (10), l'appareil comprenant :

    appareil d'acquisition d'images (18) opérant pour acquérir une image d'une partie d'un corps animal ou humain afin de fournir une image couleur numérique ;

    caractérisé en ce que l'appareil d'acquisition d'images (18) est également opérant pour acquérir une image d'une échelle des couleurs afin de fournir une image d'échelle des couleurs, et l'appareil comprend en outre :

    appareil de traitement (20) opérant pour déterminer une transformation d'étalonnage pour les couleurs d'une image acquise par l'appareil d'acquisition d'images (18) en fonction de l'image d'échelle des couleurs et des valeurs de couleur représentées dans l'échelle des couleurs, dans lequel la transformation d'étalonnage inclut des transformations pour chacune des valeurs Rouge, Vert et Bleu et chaque transformation de Rouge, Vert et Bleu inclut une palette de couleurs (LUT), dans lequel chaque LUT est déterminée en peuplant la LUT de manière clairsemée avec des différences de couleur entre chacune des valeurs de couleur dans l'image d'échelle des couleurs et chaque couleur réelle correspondante pour l'échelle des couleurs et en interpolant entre les points clairsemés,

    l'appareil de traitement (20) étant en outre opérant pour transformer l'image couleur numérique avec la transformation d'étalonnage afin de fournir une image couleur numérique à couleurs compensées (48) ;

    appareil de mélange de peinture (26) opérant pour mélanger une pluralité de peintures de différentes couleurs en fonction d'au moins une caractéristique de couleur d'au moins une couleur à l'intérieur de l'image couleur numérique à couleurs compensées (48) afin de produire au moins une peinture mélangée (60) ; et

    appareil d'application de peinture opérant pour appliquer l'au moins une peinture mélangée sur un revêtement cosmétique (10).


     




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    Cited references

    REFERENCES CITED IN THE DESCRIPTION



    This list of references cited by the applicant is for the reader's convenience only. It does not form part of the European patent document. Even though great care has been taken in compiling the references, errors or omissions cannot be excluded and the EPO disclaims all liability in this regard.

    Patent documents cited in the description